(Origins unknown)
1) A word to describe some random skank that has one purpose in life, and that’s to take a dick
2) Some chick that you would have a one night stand with, and then possibly hit it a few more times ( note: once strange is fucked more than a few times said strange becomes " Familiar)

Side note: Strange is not necessarily Smokin hot, in fact strange looks better while intoxicated in some form.

-man in car speaking to known strange- Hey ladies, rember me
-Strange with slight smirk - Yes i rember ( insert name here)
-man - I'm going back to my house to drink, what are you up to
-strange- looking for a place to drink
-man - Well lets get drunk and fuck in the hot tub
Follow me bitches, lets get some Strange! ( Peels out )

Sexual intercourse with someone outside the primary relationship. The person is strange or unique to the primary relationship.

A usage of this can be seen in the song by Kris Kristofferson's - "Gettin' By, High And Strange"
Soon as I was better I was movin' on gettin' it together gettin' good and gone
And by (gettin' by) high (good and high) and strange (gonna get some strange)